This invention relates to an improved method and means for operating an internal combustion engine so that it provides, using some of its cylinders, a hydrogen rich gas which can then be used as a fuel by the remaining cylinders.
A vast amount of research is being directed toward eliminating the nitric oxide (NO.sub.x) emissions from internal combustion engines and also for improving the efficiency of the operation of an internal combustion engine. It has been found that when hydrogen is mixed with a hydrocarbon fuel, a much leaner ratio of hydrocarbon fuel to air can be used in the internal combustion engine than would otherwise be possible, in view of the fact that the hydrogen can support combustion whereas a lean ratio of hydrocarbon fuel and air cannot support combustion. It has also been found that when the ratio of hydrocarbon fuel to air is "lean" beyond a certain point, then the amount of NO.sub.x produced as a result of a use of the mixture in an internal combustion engine is substantially eliminated. Thus lean operation results in a low flame temperature which yields low NO.sub.x.
In a patent application Ser. No. 387,342, filed Aug. 10, 1973 by Jack Rupe entitled System for Minimizing Internal Combustion Engine Pollution Emission, there is described and shown an arrangement for generating hydrogen and mixing the hydrogen with a hydrocarbon fuel and air and then injecting them into an internal combustion engine whereby the amount of NO.sub.x produced by the internal combustion engine is substantially reduced. In that application there is described and shown a hydrogen generator which produces the hydrogen for use in the internal combustion engine.
In an application for a hydrogen rich gas generator, Ser. No. 428,444, filed Dec. 28, 1973, by this inventor, there is described an arrangement for a hydrogen rich gas generator for generating gases required in the system for the type which has been described. While these hydrogen gas generators are effective for the intended purpose, they constitute an auxiliary piece of equipment, requiring peripherial service equipment such as a starting system, an air pump, etc. If a source of hydrogen rich gases can be provided without such auxiliary equipment, there could be a savings in cost and a simplification of the equipment.
In a patent to Mikulasek et al., U.S. Pat. No. 2,648,317, there is shown an arrangement for using at least one piston of an internal combustion engine into which vaporized hydrazine is injected. The piston of the cylinder is allowed to compress the mixture. Then the hydrazine is detonated by an electric discharge for the purpose of being decomposed into hydrogen, nitrogen and ammonia. The decomposition products of the hydrazine are then mixed with air to form a further explosive mixture which, when ignited, produces pressure and releases heat to be transformed into mechanical energy. The problem with the arrangement described and shown in the patent, is that hydrazine decomposes very rapidly and provides a very violent reaction which is extremely explosive and almost impossible to control. Furthermore, according to the patent, for mixing air with the decomposed products of hydrazine, a high pressure source of air is required. Since a high pressure air compressor is expensive to operate, this adds to the cost of the system.
Hydrazine is classified as a corrosive liquid, and must be carefully transported under a special label. Consequently the invention described in the patent is not believed practical for automotive application as it is much too dangerous to have any hydrazine on board.